EP 0023780 A1 19810211 - Silver halide emulsions containing a nucleating agent, photographic elements, film unit and processes for the production of direct positive images.
Title (en)
Silver halide emulsions containing a nucleating agent, photographic elements, film unit and processes for the production of direct positive images.
Title (de)
Silberhalogenidemulsionen, die Keimbildungsmittel enthalten, photographische Elemente, Filmeinheit und Verfahren zur Herstellung direkt positiver Bilder.
Title (fr)
Emulsions à l'halogénure d'argent contenant un agent de nucléation, éléments photographiques, unité de film et procédé pour former des images positives directes.
Publication
Application
Priority
- US 5658879 A 19790711
- US 12215180 A 19800219
Abstract (en)
Direct reversal photographic materials are described in U.S. Patent No. 4,030,925 which contain an acylhydrazinophenylthiourea nucleating agent having a single substituent on the N atom at the 3-position in the thiourea moiety. Improved photographic materials are now provided containing silver halide grains which are capable of forming an internal latent image and to which is adsorbed a nucleating agent of formula: <CHEM> wherein R is H or an alkyl, cycloalkyl, haloalkyl, alkoalkyl or phenylalkyl group; R<1> is a phenylene group or a phenylene group substituted with alkyl, halogen or alkoxy; and R<2> and R<3> are independently a) an alkyl, haloalkyl, alkoxyalkyl or phenylalkyl group having from 1 to 18 carbon atoms; b) a cycloalkyl group; c) a phenyl group having a Hammett sigma value-derived electron-withdrawing characteristic less positive than +0.50; or d) a naphthyl group; or R<2> and R<3> together form a heterocyclic group having a 5- or 6-membered ring; the alkyl groups, except as otherwise indicated, having 1 to 6 carbon atoms; and the cycloalkyl groups having 3 to 10 carbon atoms.
IPC 1-7
IPC 8 full level
C07D 295/215 (2006.01); G03C 1/485 (2006.01)
CPC (source: EP)
C07D 295/215 (2013.01); G03C 1/48561 (2013.01)
Citation (search report)
- FR 2410300 A1 19790622 - FUJI PHOTO FILM CO LTD [JP]
- DE 2913567 A1 19791018 - FUJI PHOTO FILM CO LTD
- DE 2635316 A1 19770303 - EASTMAN KODAK CO
Designated contracting state (EPC)
DE FR GB
DOCDB simple family (publication)
EP 0023780 A1 19810211; EP 0023780 B1 19840411; DE 3067429 D1 19840517
DOCDB simple family (application)
EP 80302365 A 19800711; DE 3067429 T 19800711